Heat a large pot over medium heat and add diced chicken.
Cook chicken until browned, about 5-7 minutes.
Add chopped onion and minced garlic; sauté until onion is translucent.
Stir in chili powder, cumin, salt, and pepper; cook for 1 minute.
Add diced tomatoes, black beans, kidney beans, and corn.
Pour in 1 cup of water and stir to combine.
Bring to a boil, then reduce heat and simmer for 20 minutes.
Check seasoning and adjust salt and pepper as needed.
Serve hot, garnished with fresh cilantro.
Enjoy your hearty chicken chili with your favorite toppings!